Panasonic FS-A1ST add 256kb RAM

This howto describes how to add an extra 256kb Ram to a Panasonic FS-A1ST to get 512kb Ram.


  • 2x 44C256 (IC31 / IC33) (I used OKI M514256B)
  • 2x SMD Capacitor 100 nF (C138 / C140)
  • 2x SMD Resistor 100 Ω (R55 /R229)
  • 1x Resistor 10 KΩ (R41)
  • (A lot of experience soldering SMD components)


First remove the mainboard from the FS-A1ST.

When removed, clear the solderpoints of IC31, IC33 and R41.

Solder Removed

Solder the SMD Capacitors on the empty spots C138 / C140 (Topside, just above the memory IC’s)

Solder the memory IC’s on the empty spots IC31 / IC33

Solder the SMD Resistor on the empty spot R55 (Top Side, left from the memory IC’s)

Memory Resistor and Capacitors

Solder the SMD Resistor on the empty spot R229

Resistor R229

Solder the Resistor on the empty spot R41

Resistor R41

Assemble the FS-A1ST and the bootscreen will show 512Kb Ram

Bootscreen FS-A1ST 512kb

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